The main band: guitar + lead vocals, bass + backing vocals, drums + backing vocals, with occasional use of live looping and other gadgets to create a big sound.
For a bigger band, options include adding second guitar/vocals, keyboards/vocals and more.
The main band, playing acoustic instruments (acoustic guitars and cajon/percussion).
Background Jazz Duo or Trio
Lightly amplified acoustic guitars and percussion playing jazz and Latin standards. Perfect for setting the mood during dinner or while guests mingle during you reception.